Electro-mechanical relays were historically discrete analog switches that were used in early computers for such applications as to implement Boolean logic. Discrete electro-mechanical relays continue in common usage for certain commercial, automotive, communications, automation, power, and other applications. Inherent advantages of electro-mechanical relays include relatively low current leakage and excellent reliability of operation.
Transistors have largely supplanted electro-mechanical relays in such applications as computers, digital logic, and communications. Fabrication of transistors, and other such devices, relies on such solid-state semiconductor processing techniques. Conventional transistors (including, for example, NMOS, CMOS, field effect transistors, bipolar transistors, or other types) have some voltage drop across their terminals that typically result in current leakage. Such leakage can result in considerable power consumption for the transistors themselves as well as their associated circuits. Additionally, transistors have difficulty operating in harsh or radioactive environments.
Therefore, there is a need in the art for switching devices having limited current leakage, as well as being able to function in harsh or radioactive environments.